Exemplary embodiments relate to a semiconductor device and a method of manufacturing the same and, more particularly, to a semiconductor device including copper (Cu) wiring and a method of manufacturing the same.
A semiconductor device includes a metal wiring system for electrically coupling individual semiconductor elements. The material of the metal wiring is to be determined by taking the electrical properties and the manufacturing costs of the semiconductor device into consideration because the signal transfer speed quite differs depending on what material is used to form the metal wiring.
In a conventional art, the metal wiring is chiefly made of aluminum (Al). However, a technique for forming the metal wiring using copper (Cu) instead of aluminum (Al) is being developed since copper (Cu) has lower resistivity than aluminum (Al) and has higher melting point than aluminum (Al). If Cu wiring is used, reliability of the semiconductor device may be increased and the signal transfer speed thereof may be increased because of low resistivity.
If the Cu wiring is used in the semiconductor device, however, the Cu wiring may be shrunk or Cu atoms of the Cu wiring may be diffused in an annealing process performed after the Cu wiring is formed. Accordingly, the Cu wiring may be disconnected or bridged. For example, a short circuit may be generated in a contact area because of tensile stress caused by the shrinkage of the Cu wiring.
Specifically, the wiring may be damaged by electron-migration (EM) generated in stress conditions of current. Furthermore, the wiring may be damaged by stress-migration generated in stress-induced conditions.
If the Cu wiring is used in the semiconductor device as described above, the reliability of the semiconductor device may be degraded because the electron-migration (EM) or the stress migration is generated.